Nitro derivative of tertiary butyl ethyl anisole



Patented Jan. 10, 1950 UNITED STATES PATENT OFFICE NITRO DERIVATIVE OF TERTIARY BUTYL ETHYL ANISOLE Thomas F. Wood, Clifton, N. J assignor to The Givaudan Corporation, a. corporation oi New Jersey No Drawing. Application July 5, 1947, Serial No. 759,299

1 Claim. 1

hydrocarbons, products possessing diflerent varieties of odor are obtained. All of such synthetic musk products which have found extensive use in perfumery contain, as far as I am aware, a methyl (CH3) group as one of the substituents on the benzene nucleus.

I have now found that a synthetic musk material can be prepared by nitrating a benzene derivative which contains no methyl group at all. The structural formula of my novel material may be represented by the following formula:

OCH:

(CHahC N0:

CIHI

While the chemical configuration of my novel musk-like material bears a resemblance to the known musk ambrette, nevertheless it was indeed surprising to find that the presence of an ethyl (C2H5) group in the ring in place of methyl (such as is the case with musk ambrette) not only does not weaken the odor of the materialas would have been supposed, but in fact actually materially strengthens the musk character of the material. This has the effect of enabling a perfumer to obtain the desired musk characteristics by using less of my novel material than would be required if musk ambrette were employed. Moreover, another distinct and unexpected advantage of my material is that it is capable of imparting an odor which is similar to that of natural musks, which are entirely unrelated chemically and for some applications considered to be superior to the aforesaid synthetic musks.

In general, I prepare my novel musk-like material by first methylating meta-ethyl phenol to produce meta-ethyl anisole; then butylating the latter by means of isobutene and a catalytic amount of aluminum chloride, to form 3-ethy1-6- tertiary-butyl anisole;. and finally, nitrating the latter at low temperature in the presence of acetic anhydride, to produce my novel musk material, 2,4-dinitro-3-ethyl-6-tertiary-butyl anisole.

A schematic representation of the chemical equations involved in my process follows:

OH O CH:

Isobuty/ 0 on, 0 on,

(CH3)3C BNO; (CHQ)3C N03 omc o)=o ozHs 23:

The methylation of the meta-ethyl phenol is accomplished by means of dimethyl sulfate and aqueous sodium hydroxide, in accordance with known procedures.

The butylation of the meta-ethyl anisole can be carried out by slowly feeding isobutylene into a chemically-equivalent amount of the metaethyl anisole at 20-25 0., in the presence of about 2 to 3% of anhydrous aluminum chloride powder as catalyst. The amount of anhydrous aluminum chloride used is based on the weight of meta-ethyl anisole.

The nitration of the 3-ethyl-6-tertiary-butyl anisole is conducted at temperatures within the range of 20 C. to +20 C., in the presence of 1.5 to 2.5 times its weight of acetic anhydride, using 2 to 3 times the theoretical amount of 96- 98% fuming nitric acid. It has been found desirable to feed the B-ethyI-G-tertiary-butyl anisole into a mixture of nitric acid and acetic anhydride rather than reverse the procedure, in order to avoid the formation of tarry by-products.

Upon completion of the nitration, the crude product is obtained by quenching the reaction mixture on ice and then filtering. The crude nitration product is then washed until neutral The invention is: illustrated by thewfollowiri example without howeveflimiting 'the's'ame to it;

EXAMPLE (a) Preparation of metfi eflizjfa'rtisoleh -1iitio'n; iwa-rming with ten.; times its Weight of textile In a mixture of 418 gramsa(B .43 moles5 -.of pure meta ethyl phenol and 300 g-faifls t2z38 mole's of dimethyl sulfate, cooled to 20 C. in a suitably provisioned apparatus, was slowly fed-with stirring-.1 1,075 grams of a 16.5% aqueous caustic soda scr lution maintaining the temperature below 30 C.

Then, the mixture was stirred 1 hour atr'oorfi" temperature and 9 hours at 95 C. The upper layer 'wasithen' settled,- iseparated arrd extracted' s thoroughly with.2:5 caustic "soda-solution and washedwith water. The: product was: v'acuu'm" distilledto' give "388 grams offimet'a ethyl anisole-- Y (b) Prepardtiow ojlfi-ethyl fi atefitiaryebutyl anisole Into a flask provided 'with-a thermometer, efficient agitator and gas inlettube was charged:

Meta ethyl anisoletM. W.=136) 328grams (2.41 moles) Aluminum chloride powder 10 grams c: There was reco'vere iri 115 "grams fornrethyfani- 7 There was obtained 67.7 grams of this eproduct' I Number V 4 I (0) Preparation of 2,4-dinitro-3-ethyl-6-tertiari butyl anisole A cold mixture of 82.1 grams (0.428 mole) of 3-ethyl-6-tertiary butyl anisole and 41 grams of acetic anhydride was slowly fed with stirring into a solution of ,10 C. of 138 grams (2.15 moles) of 98% nitric acid and 123 grams of acetic anhydride. The temperature was maintained at 0 to +5 C. during the feeding and the time of feeding. was-1-hour and 15 minutes- Toward the end of thje nitration,.crystalsfiappeaireii the mixture and at the end the contents of the flask was a zgreenish-yellow crystalline mush. The product was quenched on crushed ice and then filtered a rfdwashed rieutiakwith water and soda ash so- The crude product was dissolved by spirits This-solution on cooling deposited crystals of a light yellow powder insoluble in cold textile spirits. This compound is a by-product and rrielted"at88" (Ii-89 C. The textile spirits solution was evaporated and the reddish yellow residue'cry'stallized from four times its weight of alcohol. The product wasF'obtained in the form of fine pale--yel low--need1es, -melti-ng point=77 which hadastrong: persistentodor of musk.

fora' Weigh-t yield of 82.5%;

-This novel product can be employed as an ar: tificial musk in :perfumery-in-"genera-l, and has particular usefulness"-in--sperfumesemployed in;

Theforegoingillustrates-the practice of this-2 irrventiom which however, gis ncit'to- "b mie;

thereby but is-*tobe construed as broadly =as.:pr=" missiblein View of: the prior-art and limited solely:i byathe appended claimo v:I claim:

e2;4 -dinitro-3-ethyl --6-- tertiary.- butyl" anisoleew. comprising yellow crystals havingra meltin'g point of 7 7 C-. andpossessing: astrong persistent musklikeiodorn.

. 1 THQMAS WOOD.-

, REFERENC'E'S CiTEDf The following references are of record in the file of this patent:

UNITED srArEs -'PATENTS Name Date 481,685 Bauer"; Aug. 30, 1892 1,926,080 Borman'- Sept. 12, 1933 2,007,2 8? Wirth July, 9, 1935 2,007,235 Dgltlolnfetali July 9,1985 221 661917 

